Five species of Gnathostoma are at present reported from Southeast Asia with specific diagnostic characteristic of each. Also important references relating to the specific characters of the species concerned were mentioned, and the known experimental life cycles of three species namely G. spinigerum, G. hispidum, and G. doloresi found in the region were compared. The incomplete experimental study on the life cycle of G. vietnamicum is presented but the investigation on the life cycle of G. malaysiae is not yet initiated. Methods of transmission, symptoms and signs, the diagnosis and treatment of animal and human gnathostomiasis were also summarized. Effective therapeutic value of many anthelmintic drugs has not been satisfactory, by screening test on white mice previously infected in the tissue with G. spinigerum larvae. However, successful result of treatment was reported on one Japanese gnathostomiasis patient with thiabendazole. In the treatment of animal gnathostomiasis, Ancylol disophenol seems to be he effective drug for eliminating adult and migrating stage in the experimentally infected cats. Brief preventive measures against human gnathostomiasis was mentioned.